Thanks,
For long route, i have driven it on motorway only once with 5-persons on-board, it has given me 22km/ltr with a speed of 90-100 km/h.
And now it is driven only within Islamabad/Pindi and giving 18-22 km/ltr on light foot with speed of about 80km/h.
But if you drive at 100-120km/h, then it given about 15-16 km/ltr.
So, it all depends upon the driving style.